1. Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
2. Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford , OX1 3SY, U.K.
3. Laboratory of Pathophysiology, Butantan Institute, Av. Vital Brazil, 1500, 05503-900 São Paulo, Brazil
4. Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, 05403-000 São Paulo, Brazil